def sum_of_divisors(n):
    # 初始化真因子之和
    sum_divisors = 0
    # 遍历从1到n-1的所有数，检查它们是否是n的因数
    for i in range(1, n):
        if n % i == 0:
            sum_divisors += i
    # 判断真因子之和是否等于n
    if sum_divisors == n:
        return "yes"
    else:
        return "no"

n = int(input())
print(sum_of_divisors(n))
